Talk about nostalgia for old-fashioned food. While some people nurse memories of grandma's cooking, the anthropologist Dr. Lionel Tiger's fixation is cave man food -- Upper Paleolithic cave man food, that is, from 10,000 or so years ago, the dawn of civilization. And like it or not, he says it's what we long for, too.

We are drawn to the campfire and tempted by the "newly traditional barbecue, with its particular primordial attention to the taste of smoke -- always surrounded by the magnetic aroma of charring fat," he insists in his new book, "The Pursuit of Pleasure" (Little Brown; $22.95).

The book is a lively, thought-provoking study of alimentary, sexual, emotional and other pleasures -- and vices -- sometimes putting human nature on a collision course with contemporary post-industrial society.

Dr. Tiger, the son of a grocer, is a soft-spoken cherubic-looking man of 54. He discussed his theories over dinner last week, setting a good Upper Paleolithic example by cleaning his plate of charred lamb salad before moving on to the roasted halibut.

The name Tiger is of Latvian origin; "Lionel" was decided on by his parents, who, he said, wanted a name that began with an "L" -- they decided that Leonard Tiger just didn't have the right roar.

"The fact that I was the youngest, smallest and most cowardly boy in my class growing up in Montreal, a tough town, did not help," he said.

He is an anthropologist specializing in the study of the evolution of behavior -- the Charles Darwin professor of anthropology at Rutgers University -- and his name has made for some odd coincidences.

Better believe that he actually worked with a photographer named Reinhart Wolf and a colleague, Robin Fox. "I met him at the London Zoo," he said with a straight face.

Not surprisingly, they collaborated on a book called "The Imperial Animal" (Henry Holt, 1971), a study of the sources of violence and aggression that focused on human nature and the traits that have always characterized it.

Dr. Tiger's first book, "Men in Groups" (Random House, 1969), explored the notion of male bonding. "It amuses me to think of the impact I've had on the movie industry," he said.

Some of the ideas Dr. Tiger has explored in his new book grew out of "The Imperial Animal." "There is something eternal in the human situation," he said, "and cultural differences are merely variations on a common denominator."

Take food. "My colleagues say that what we eat has to do mostly with culture, but it's more than that," he said. He called the era at the dawn of civilization a nutritional golden age in which the cardiovascular system, the taste buds and the food supply were in harmony.

It was a time the human body remembers, and that imprint still controls the way it functions.

These days, he said, we eat a rich meal and then go jogging to recapture that Upper Paleolithic metabolism because human bodies have not adjusted to a different way of life.

"In 10,000 years, you can't change cholesterol and the whole cardiovascular system," he said. "If you think about all the foods we now consider to be unhealthy, like butter and beef, they are foods that came about after man made the transition from hunter-gatherer to shepherd and farmer."

The taste buds, a survival tool, were also formed in the era of the hunter-gatherer. Simply put, distastefully bitter and sour flavors served to warn early humans away from unripe fruit or plants that might even be poisonous. A sweet taste was a signal that the fruit was ripe and safe.

Now, however, the body's desire for sweets -- like its taste for fats -- is too easily satisfied, in what Dr. Tiger calls a "maladaptation" of relatively recent vintage.

Before the late 17th century, sweets came mostly from fruit because sugar as such was not cultivated -- and it took a lot of fruit to provide a sugar blast equivalent to that from a can of soda or a couple of brownies.

"The old preferences and pleasures produce new problems," he said.

What is needed, he contends, is a more balanced view of the pleasure of eating. That sugar is considered a treat today, Dr. Tiger writes, implies that the rest of what we eat is not.

The lust for sugar, along with a struggle to control it, has taken over because "we are reluctant to celebrate the pleasure of food," he said.

"It's a pleasure denied by experts who have promoted a theory of modernization, hygiene and emancipation from nature," he said. He means the nutritionists, industrial food producers and scientists.

He complained that schools teach music and art appreciation, but not an appreciation of food. "The four food groups are never called wonderful, delicious, tasty and scintillating," he said.

High on his list of egregious food policing was the recent ban in New Jersey of runny or soft-cooked eggs. Dr. Tiger called the ban, which was imposed to guard against possible salmonella contamination, "fascist: the result of busybodies who feel they can control the destiny of their fellow man."

It might be more worthwhile, he said, to prohibit the use of TTC powdered eggs, which he termed esthetically unfit to eat.

For Dr. Tiger, it's essential that food taste good. "We have a lot to answer for when it comes to our children and their nutrition because we have not treated their need for tasty food with enough seriousness," he said.

He contrasted the American "children's portions" with the Chinese system of eating, with food cut in small pieces and served on communal plates. "No children's portions," he said. "Children can eat what they want and are not humiliated."

He also said that Chinese markets, where seafood and birds are sold live, more easily satisfy that old longing for the Upper Paleolithic era of the hunter.

"When I was in China and told people how we bought fish in our shops, they were aghast," he said. "They couldn't understand why anyone would buy a dead fish."

He pointed out the increasing appeal in this country for primordial food displays. "A perfect row-house hygiene yields to vivid and lucid displays of naked food," he wrote in "The Pursuit of Pleasure."

Cans of soup do not tout the fact that they're factory-made but that they're like the homemade article, he said. "The operators of industrial-style food stores were surprised that people enjoy ways of selling food that are nostalgic, even primitive," Dr. Tiger wrote; of course, he would expect it. "We are beginning to come around to the belief that nature has value."

Sharing the food that was acquired in the hunt was essential for primitive humans to maintain community health and availability of food. Restaurants are popular today, he said, because they are intense food-sharing enterprises, necessary now that the home is losing its traditional importance as a place where food is prepared and served to a group.

He said eating alone represents a breakdown of man's "fundamental humanism" and something most people prefer not do, given the choice. Dr. Tiger, who is divorced and has a 22-year-old son at Yale, selects his meals the way "more serious people select investments."

Dr. Tiger, it should be noted, has a rather Utopian vision of what society could accomplish if pleasure were nurtured rather than constantly restrained. "There's something intrinsically sensible in the idea that what pleases nearly all people must have helped most of their ancestors endure," he said. Sexual pleasure. Good food.